A lower Manhattan parking garage prevented customers from fleeing Hurricane Sandy when it locked its facility without warning just before the storm made landfall, a Manhattan class action lawsuit charges.

About 50 cars were held captive, only to be totaled by floodwaters, the suit claims.

One man who tried to retrieve his Infiniti to evacuate his wheelchair-bound daughter — but he found the gate shuttered, the filing stated.

“They put people’s lives in jeopardy,” said Carmelo Aviles, 47, whose 23-year-old daughter is paralyzed and was stuck in the family’s seventh story apartment without heat or electricity for five days.

Attendants at the 24/7 garage, at 227 Cherry St., repeatedly assured customers that it would remain open throughout the storm, papers state.

“We are not closing,” an attendant told several monthly customers just after Mayor Bloomberg announced a mandatory evacuation for the area, the papers state.

By 4 pm on Oct. 28, the garage was locked and protected from the surge by a only four, 3-foot sandbags, the filing states, and the company ignored repeated pleas from customers trying to access their vehicles.

Customers were finally allowed in Nov. 9 and only after they signed a liability waiver. Some of the car owners had comprehensive insurance, others did not. Owners also lost personal property ranging from car seats to GPS devices. The suit is seeking unspecified damages.

Michael Wolf, an executive at Standard Parking, said the “hurricane did, of course, have a significant impact on the 227 Cherry St. parking facility.” He declined to comment on the pending lawsuit.